SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'cbfbb4751052e5f5ec93743e39035ffacce445b27eb26dd3e8b97bab1769b790' 
  AND token = 'n9jiQLXXyNDM34psce6ht8Lbkw3NiPQgyoRujHhBcdA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}